Etoposide is a topoisomerase II inhibitor. It is also available as etoposide phosphate. Etoposide inhibits the entry of tumor cells into mitosis, which is why it is used, in combination with other chemotherapy agents, for the treatment of certain cancers such as lung cancer, testicular cancer, certain lymph and leukemias, and glioblastoma.

Toposimerase II inhibitors such as etoposide have been shown to be effective in the treatment of cytokine storm caused by lymphohistiocytosis haemophagocytosis (LHH). These inhibitors have also been shown to suppress the replication of RNA viruses in vitro. The toxicity profile of topoisomerase II inhibitors in patients with LHH does not translate in severely ill patients because COVID-19 and LHH have fundamentally different causes of their respective cytokine storms: an over-stimulated innate immune response is the cause of cytokine storms in COVID-19 infection, while an over-stimulated adaptive immune response is the cause of cytokine storms in LHH. Etoposide could be used in combination with irinotecan a topisomerase I inhibitor for effective action against SARS-CoV-2 coronavirus.